1. Field of the Invention
The invention is directed on a decoupling device for actuators.
2. Description of the Prior Art
During operation of the actuator—in particular an electric motor which, by means of decoupling elements, is connected to a function housing via a decoupling housing—tangential rotary oscillations are produced, for example in a main excitation oscillation direction of the actuator, and oscillations are produced in the radial and axial directions. For a decoupling between the actuator and the decoupling housing, this means that they must be particularly soft in the tangential direction and must be significantly more rigid in the axial direction and radial direction.
Decoupling devices for actuators and electric motors are known, but these are relatively rigid. Running noise of the electric motor and running-induced oscillations of a fan connected for example to the electric motor, e.g. due to an imbalance of the impeller, are largely transmitted to a fan housing and lead to an undesirable generation of noise.
With elastic decoupling elements which on the one hand are intended to hold the actuator or the electric motor in support regions and on the other hand are intended to achieve a damping, these conflicting demands result in the fact that the decouplings are placed under initial stress. Since the damping of oscillations takes place through flexing work in the decoupling elements, an optimal decoupling is not possible.
In addition, the decoupling elements are adjusted in terms of their natural frequency so that a natural frequency of the decoupling element differs significantly from a natural frequency of the actuator. The damping can as a result be partially increased.
EP 0 682 396 A2 has disclosed the use of elastic balls, preferably comprised of an elastomer, in order to decouple two components from each other. The balls are each accommodated in an ellipsoidal cavity so that the balls permit a certain amount of free rotational movement. Each component has cavities of this kind so that the cavities of the two components are disposed opposite each other after assembly. The cavities are let into an intermediary piece.
However, the device requires a central securing element and for damping, requires another elastic element which is disposed around a longitudinal axis.